Envelope closing devices



Nov. 21,1967 H. SCHMITT 3,353,513

ENVELOPE CLOSING DEVICES Filed June 10, 1965 w 5 Sheets-Sheet 1 Nov. 21, 1967 H. SCHMITT 3,353,513

ENVELOPE. CLOSING DEVICES Filed June 10, 1965 3 Sheets-Sheet 2 lNV/W'OR am 50 M177 Nov. 21, 1967 H. SCHMlTT ENVELOPE CLOSING DEVICES Filed June 10, 1965 3 Sheets-Sheet 5 INVENI'O'? 1%: 5K/U/f/f 1, Mmd Mk 17770? //[y5 United States Patent Office 3,353,513 Patented Nov. 21, 1967 3,353,513 ENVELOPE CLOSING DEVICES Hans Schmitt, Frankfurt am Main, Germany, assignor to Telefonbau und Normalzeit G.m.b.H., Frankfurt am Main, Germany, a joint-stock company of Germany Filed June 10, 1965, Ser. No. 462,930 Claims priority, application Germany, June 24, 1964,

T 1 Claim. (Cl. 118-32) ABSTRACT OF THE DISCLOSURE The present invention relates to envelope closing de- VlCeS- Envelope closing devices are known in which envelopes conveyed mechanically are passed over a moistening tongue. This moistening tongue carries on its side facing the gummed flap of the envelope a felt or sponge strip connected to a water tank for transferring moisture to the gum so that when the flap is subsequently pressed down onto the envelope the envelope is securely closed.

When the envelopes are fed at high speed, difliculties may occur since the envelope flaps may not run correctly under the moistening tongue, the envelope flaps may not be fully moistened or the envelopes may be caught up on the moistening tongue.

It is accordingly an object of the present invention to provide a novel and improved envelope closing device which ensures that the flaps of the envelopes run correctly past a moistening tongue.

A further object of the present invention is to provide novel and improved means for fully and correctly moistening the flaps of envelopes.

A still further object of the present invention is to provide a letter closing device which avoids obstruction of letters by a moistening tongue.

According to the present invention, in the path of movement of the edges of the envelopes on which the flaps are provided a pivotable finger provided with a roller and biased by a spring is mounted so that the roller presses against the edges of the envelopes. By this pressing on the edges of the envelopes carrying the flap a space is formed for the moistening tongue in the corner between the rear surface of the envelope and the flap so that the moistening tongue can enter without resistance between the envelope and the flap.

Further features, objects and advantages of the invention will be more readily apparent to those skilled in the art from the following description of the invention given by way of example with reference to the accompanying drawings, wherein:

FIG. 1 shows an envelope closing device according to the present invention in perspective view;

FIG. 2 shows a plan view of the envelope closing device of FIG. 1;

FIG. 3 shows the envelope closing device of FIGS. 1 and 2 with a device for feeding envelopes thereto.

As shown in FIG. 1, a water tank 2 is fixed beneath a plate 3. The plate 3 has an opening 4 into which support lugs 6 and 7 of a moistening tongue 5 project. The lugs 6 and 7 have borings 8 and 9 which receive support pins (not shown) secured to the underneath of the plate 3, and on which the moistening tongue 5 is thus pivotally mounted.

On the underneath of the moistening tongue 5, there is secured a sponge strip 10. One end of the sponge strip 10 projects into the tank 2 and absorbs water.

A finger-shaped arm 12 (FIG. 2) is pivotally supported on a fixed support pin 18. The arm 12 carries a lug 14 with an adjustment screw 15 which co-operates with a fixed abutment 20. The arm 12 is biased by a coil spring 13 arranged around the pivot pin 18.

At its free end, the finger-like arm 12 carries a pin 16 on which a rotatable roller 17 is arranged. This roller 17 is preferably formed as a double-cone roller with conical surfaces 24, 25, the smallest cross-section of the roller being disposed at the same height as the moistening tongue 5, i.e., in the same plane as, and thus in alignment with the tongue 5. The roller 17 is drawn by the spring 13 into the path of movement of the edge of the envelopes at which the flap is formed. The envelopes to be closed are fed by a traveling belt 30 from a stack 31 (FIG. 3) and before each of the envelopes reaches the moistening tongue 5 it runs beneath a pressing lever 23 which is mounted on a fixed pin 32 and is biased by a spring 33. This sprung pressure lever 23 lies in the vicinity of the path of the flap-carrying edges of the envelopes to be closed and prevents upward deflection of the envelopes.

As soon as each envelope has reached the position occupied by the envelope indicated by reference numeral 21 in FIG. 1, in which the roller 17 presses against the edge of the envelope carrying the flap, a space is formed between the rear side of the envelope and its flap 22 by the pressure of the roller 17. The envelope flap 22 runs beneath the moistening tongue 5 and its gummed edge is moistened by the Wet sponge strip 10.

After the envelope has passed over the moistening tongue 5, it arrives at a pressure roller (not shown) which presses the moistened flap in known manner against the rear of the envelope.

The roller 17 on the finger-shaped arm 12 is preferably made of friction-resistant plastics material.

I claim:

An envelope closing device comprising a moistening tongue for moistening the gummed flap of an envelope, a pivotable element, an abutment for said pivotable element, spring means urging said pivotable element towards said abutment, means for adjusting said pivotable element to co-operate with said abutment, a double-cone shaped roller rotatably mounted on said pivotable element with the smallest cross-section of said roller in the plane of said moistening tongue, said roller being disposed before said moistening tongue in the direction of travel of said envelope and said spring means being adapted to urge said roller against the flapped edge of said envelope to form a gap between said envelope and the flap thereof for receiving said moistening tongue, and a pressure lever disposed before the moistening tongue in the path of advance of the flap-carrying edge of said envelope for preventing upward deflection of said envelope as said envelope reaches said moistening tongue. 

